The limiting factor in braking is your tires -- they determine how much traction you have.
You are therefore able to brake harder (and stop/slow down in shorter distance) with race tires, and are generating that much more kinetic energy into heat.
Neil

Yes, the limiting factor for braking is the tires.

But your statement is not quite correct. The amount of heat going into the brakes is purely determined by the mass and the velocity. So, if you are slowing down from 100 to 50 and the mass is the same, you are creating the same amount of heat for the brakes to dissipate. The tires don't make a difference. Although, with good tires, you will not be slowing down as much for a corner, so there should actually be a little less heat going into the brakes.

Best way to make your brakes last longer at the track is to slow down less. The faster you are in the corners, the longer your brakes will last.

But your statement is not quite correct. The amount of heat going into the brakes is purely determined by the mass and the velocity. So, if you are slowing down from 100 to 50 and the mass is the same, you are creating the same amount of heat for the brakes to dissipate. The tires don't make a difference. Although, with good tires, you will not be slowing down as much for a corner, so there should actually be a little less heat going into the brakes.

Best way to make your brakes last longer at the track is to slow down less. The faster you are in the corners, the longer your brakes will last.

Fair enough, and I certainly agree with your last point.

Nonetheless, assuming the op is an intermediate or advanced driver, I don't know why he would have imagined that the stock pads would be sufficient -- especially if he was running race tires.

If your rotors continue to have accelerated wear or warping with street or race pads, have a look at the PFC Direct Drive rotors, they will run much cooler and last longer. They are also about 4.2 lighter per rotor!

If your rotors continue to have accelerated wear or warping with street or race pads, have a look at the PFC Direct Drive rotors, they will run much cooler and last longer. They are also about 4.2 lighter per rotor!

But your statement is not quite correct. The amount of heat going into the brakes is purely determined by the mass and the velocity. So, if you are slowing down from 100 to 50 and the mass is the same, you are creating the same amount of heat for the brakes to dissipate. The tires don't make a difference. Although, with good tires, you will not be slowing down as much for a corner, so there should actually be a little less heat going into the brakes.

Best way to make your brakes last longer at the track is to slow down less. The faster you are in the corners, the longer your brakes will last.

The situation re heat build up is, I believe, a little more complicated than either of you are giving it credit for. Not to belabor, but heat dissipated by brake in a given corner will be determined by kinetic energy delta for the car. This would not necessarily be less with higher corner speed as will have higher entry speed as well and as far as fade is concerned, the shorter lap times will lead to less time to dissipate the heat (ie, you will be quicker on the straights too.) But certainly if higher corner speed allows no or less braking you will be better off!

I have finally fitted Pagid Yellow RS19 pads and driven perhaps 100km since, trying to brake hard from speeds of up to 120km/h. Unfortunately my vehicle (front) still vibrates and shudders. Furthermore, there appears to be much squeal when the brakes are applied gently at low speeds eg 10-20km/h.

How long does it take to remove the deposits and re-establish smooth braking? Or is this now likely to be a rotor issue?

I really don't think you can warp these rotors. I would recommend cleaning the rotors with a scotch brite pad with some brake cleaner then rubbing them with some really fine sand paper in an effort to rid the rotors of the deposits. That's what I did and it improved, but the issue wasn't completely eradicated until some aggressive driving with more aggressive pads (high speed bed in process and a 2 day track day have done the trick).

I really don't think you can warp these rotors. I would recommend cleaning the rotors with a scotch brite pad with some brake cleaner then rubbing them with some really fine sand paper in an effort to rid the rotors of the deposits. That's what I did and it improved, but the issue wasn't completely eradicated until some aggressive driving with more aggressive pads (high speed bed in process and a 2 day track day have done the trick).

Hope this helps.

Don't waste your time with sand paper or scotch brite. Since you've already have the Pagid pads on the car use the technique given in StopTech's Technical White Paper site. Their method works much better and faster.